Trends in fashion are always coming back, or so the old saying goes. But as heads turn towards London fashion this month, one trend from the world of Westminster is already growing rather tiresome – the relentless criticism of “retail devil in carnet” Sir Philip Green.

Labour MP and chairman of the commons business committee Ian Wright is the latest to weigh in, stating that Green should “do the right thing” and support former staff whose pensions are under threat. Wright is not the first, and certainly won’t be the last MP to lament the Top Shop moguls management of the BHS pension scheme. But one can’t help feel there are a few important financial factors being glossed over by Wright and the rest of the political class.

Firstly, under Green’s management, BHS met the trustees request for £10m to be contributed after an audit in 2012. The present value of the liabilities of the scheme doubled in the space of twelve years. This added roughly £320 million to the liabilities the scheme was expected to cover. This very scheme, much maligned over recent months, was actually in surplus both in 2002 and 2008, only to suffer colossal losses at a time when equity markets tumbled. For a scheme that was invested in anything between 50-60 per cent in equities at the time, this was highly damaging for the value of the assets. And Green’s wouldn’t have been the only scheme to have been hit by market forces during this period.

But perhaps the most important point came in 2015 when the present value of the liabilities mushroomed after the portfolio asset allocation significantly altered. All in an attempt to reduce the holdings in equity. Although it did reduce risk levels, the low returns available on bonds at the time meant Green’s fund had to buy more bonds than it would have to have done in the past to cover the liabilities.

Unfortunately, despite these facts, once MPs jump on a trend they think will increase their popularity, it is an uphill struggle to get an alternative view heard. Green is clearly no saint, but is it really the job of Government to tell him to deal with this pensions deficit? If it is, and apparently many think so, then surly the business committee needs to consider arguments from all sides – not just the one that happens to be in vogue at the time.

By Tim Focas, director of financial services for City think tank Colloquium